WO2011/011799 discloses shading dyes containing an anionic group covalently bound to alkoxy groups for use in laundry detergents to whitening textiles.
In liquid detergent products, shading dyes are used to shade white textiles. Shading dyes provide a vibrant colour to the detergent. In use, liquid detergents are frequently spilled or dripped onto hard surfaces such as washing machine tops and floors. They frequently drip down the outside of their containers and residues are left in dosing caps. The bright blue/violet colour given by the shading dye makes these unwanted spillages highly noticeable; this is especially the case with white goods. A method to reduce the visual impact is required.